Electric annunciator-drop.



Np. 7|4,7sq. Pateuiad Dec. 2, I902.

E. G. THOMAS. ELECTRIC ANNUNGI ATOB DROP.

(Application filed Max". 29, 1900. Renewed June 3, 1902.)

(No Model.)

WITNESSE J NVENTOR m: NORRIS PETERS 00,. PHOTLLLITHQ. WASNINOTUN. u. c.

UNITED STATES TATIENT OFFICE.

EDWARD G. THOMAS, OF CAMBRIDGE, MASSACHUSETTS, ASSIGNOR, BY

MESNE ASSIGNMENTS, TO ELECTRIC GAS LIGHTING COMPANY, A COR PORATION OF MAINE.

ELECTRIC ANNUNCIATOR-DROP.

SPECIFICATION forming part of Letters Patent No. 7 4,760, dated December 1902- Applieation filed March 29, 1900. Renewed June 3, 1902. Serial No. 110,060. (No model.)

To all whom it may concern.-

Be it known that L'EDWARD G. THOMAS, a citizen of Cambridge, in the county of Middlesex and State of Massachusetts, have invented 5 certain new and usefullmprovements inElectric Annunciator-Drops, of which the following is a specification.

My invention is an electric annunciatordrop for showing a visual signal of the closing of an electric circuit atsome remote point and is adapted for all the uses to which such instruments are put-as, for instance, the in- "dication of signals from the rooms in a hotel or house, in connection with fire-alarm sys-' I tems, or for any other use where it is desirable to indicate the particular circuit of a group of circuits from which the signal comes. It is especially simple in construction and of slight cost.

I will describe the invention in connection with the drawings which accompany and form a part of thisspecification. These drawings are of conventional form, and the particular form of parts and other details of construction may be modified to any extent necessary for convenience and'cheap commercial construction.

Figures 1, 3, and 4; are three front elevations of the device during its operation. Fig.

2 is a side elevation of the device when in the position shown in Fig. 1.

Upon a supporting-frame 1, preferably formed from one piece of metal, as shown in the drawings, is mounted a magnet 2. Be-

.neath the lower end of magnet 2 is pivoted an armature 3 upon pivots 4: and 5. Projecting downward from armature 3 is a catch 6 of such'a length that when armature 3 is in its lowest position catch 6 will reach and rest 40 against the lower edge offrame l. In the drawings a recess 7 has been provided to adjust the position of the armature and catch in which this occurs. The hole in frame 1, through which pivot 5 passes, is of the same 5 diameter as that of the pivot 5 or only so little larger as to allow the pivot to turn freely therein. 0n the other hand, pivot 4 passes through a hole 8, which is slotted in the directionof a line passing from this pivot to the for the indication of the signal. consisting of a suitable support 10 and a slidlower edge of frame 1 at the point where catch 6 touches it.

Secured to armature 3 is a target 9, serving A setback ing rod 11 is provided to engage the target 9 and raise it, after it has fallen,-to the position I in readiness for the indication of another signal. for limiting the downward motion of the tar- A stop 12 upon the framel is provided get 9.

The armature 3, pivots 4 and 5, catch 6, and target 9 can preferably be made from a single 'piece of sheet metal punched in suitable form and bent to the indicated shape; but these parts may of course be made sepa- 6 rately and joined together in any convenient manner. In any event they form a singleand'integral unit, moving together and having no relative motion.

The operation of the device is as follows: The parts in Fig. 1 are shown in the set position of the annunciator in readiness to receive a signal. The circuit of the magnet having been closed presumably at some distant point, magnet 2 will attract armature 3 7; andilift it into the position shown in Fig. 3, thereby raising catch 6 above the level of the bottom of frame 1. As long as the circuit is closed the magnet will hold'the parts in this position; but as soon as the circuit is broken 8c target 9 will fall toward the right to the position shown in Fig. 4, where the catch 6 is resting against the stop 12, so indicating the receipt of a signal on the circuit connected with magnet 2. Now by raising the setbackrod 11 target 9 will be raised, pivoting about pivots at and 5 until catch 6 has passed beyond the edge of frame 1. The weight of this side of the armature will then cause pivot 4; to slip to the bottom of the hole 8 and the 0 tip of catch 6 will drop below the bottom of frame 1, and the parts will then be held in the position of Fig. 1 again and can only be released by raising armature 3 by the magnet.

In order that, catch 6 may not drop back into 9 5 recess 7 when the magnet-circuit is broken after the parts assume the position shown in Fig. 3, it is advisable to make the angle between the plane of the armature 3 and that of the catch 6 such that when armature 3 is held by the magnet the tip of catch 6 will be carried slightly to the left of the edge of recess 7, as is shown in Fig. 8. When the armature is released by the breaking of the circuit, the tendency is very strong for the overbalancing-weight of the target 9 to turn the movable part about the pivots before anything else occurs; but even should the armature drop down before target 9 has time to fall catch 6 will not engage the edge of frame 1 and be held in its upper position. The drop itself may be supported in any of the ways in which annunciators are ordinarily constructed. It may be secured to a plate by its back, said plate being painted dark and having an opening, where the target will cover it only in its lowest position, so that if the target is painted white the signal will be given by the indication of a white spot at a particular opening. If an indication by a swinging arrow is preferred, such an arrow may be secured to the end of pivot 5 and by turning from one position to another will indicate the desired signal. Such parts of the construction do not constitute a part of my invention,and are therefore not claimed. The target 9 will preferably be located at the end of the armature away fromthe catch 6, since in this case magnet 2 will not have to lift the weight of the target 9, but will only have to lift that of the armature 3 and catch 6, so that a much smaller magnet will serve for the work. The setback also should be arranged to work upon the target 9 rather than upon the other end of the armature, since the loosely-pivoted end of the armature will then be free to drop into place as soon as the catch 6 has passed beyond the edge of frame 1. when the .drop is being set back into place. It is not necessary that pivot 5 should be closely pivoted, and as much freedom as is found desirable may be left at this point; but I think that the best construction will be obtained by making the hole about the size of the pivot.

Having thus fully described my invention, what I claim, and desire to secure by Letters Patent of the United States, is-

1. In an electric annunciator-drop,the combination with a magnet and a support therefor of an armature pivoted to said support below and to one side of said magnet, and tending to fall away therefrom by turning on its pivots, said support being slotted to receive one of the pivots of the armature, a catch carried by the armature and a stop therefor, said catch being arranged to' be withdrawn from its stop by a non-rotational movement of the armature lengthwise of said slot, and an indicating device movable with said armature, substantially as described.

2. In an electric annunciator-drop, the combination with a magnet of a pivoted armature carrying an indicating device, one of the pivots of the armature being vertically movable, a catch carried by the armature, and a stop for said catch adapted normally to hold the armature in proximity to the pole of said magnet, and at an angle with respect to the face of said pole, whereby the attraction of the armature against said pole iscaused to give the former a partial rotation sufficient to carry said catch back of said stop, for the purpose set forth.

3. In an electric annunciator-drop, the combination with a magnet and a support of an armature pivoted to said support and carrying a catch and an indicating device, said support being slotted to receive the pivot on that end of the armature at which said catch is located, and a setback arranged to engage said armature at that end which is oppositev to said catch, substantially as described.

4. In an electric annunciator-drop, the combination with .a magnet and a support of an armature pivoted to said support and carrying at one end a catch and at the other end a target serving also as an operating-weight, said supportbeing slotted to receive the pivot on that end of the armature which is opposite to the target, and a setback arranged to engage and operate said target, substantially as described.

5. In an electric ann unciator-drop, the combination of a frame U-shaped at its bottom and supporting a magnet from its top, and an armature pivoted in the sides of the U- shaped bottom of said frame, and provided at one end with a catch adapted normally to engage the bottom of said frame, and at its other end with an operating-weight and an indicating device, the side of the frame next to said catch being slotted to receive one of the pivots of the armature, substantially as described.

EDWARD G. THOMAS.

Witnesses:

W. E. SMITH, F. E. ROBERTSON. 

